The transmembrane orientation of the hepatic membrane receptor for asialoglycoproteins has been demonstrated. Coated vesicles have been isolated from rat liver and characterized biochemically and by electron microscopy. Radiation inactivation of plasma membranes has revealed a functional molecular weight of 104,000 for the rat liver binding protein. Receptor for the haptoglobin-hemoglobin complex has been solubilized and partially purified.